WO2007049974A1

WO2007049974A1 - Fluid cooling means and method

Info

Publication number: WO2007049974A1
Application number: PCT/NZ2006/000272
Authority: WO
Inventors: Murray James Kite; Rodney Mitchell Innes
Original assignee: Murray James Kite; Rodney Mitchell Innes
Priority date: 2005-10-28
Filing date: 2006-10-27
Publication date: 2007-05-03

Abstract

A cooling system includes a plurality of sets of teat cups connected through individual lines (2) with a vacuum header (3). Heat exchangers (17) are provided about each of the lines (2) so as to extract thermal energy from the milk substantially immediately after it has left a cow, to therefore minimise problems associated with the milk staying too long at the cow's body temperature. A further heat exchanger (11) may be provided to further cool the milk before it is received in a vat (13). The heat exchangers (11, 17) may both utilise helically corrugated conduit or other types of arrangements as a heat transfer surface.

Description

FLUID COOLING MEANS AND METHOD

Background

The present invention relates to a fluid cooling means and method and particularly to a system and method for use in cooling milk. The present invention will be hereinafter described in respect of its use in cooling of milk but it will be appreciated by those skilled in the engineering arts that the present invention could have application wherever the cooling of a fluid, whether it be liquid or gas, may be required.

In the milking of cows there is a problem with milk staying too long at the cow's body temperature within the pipe work leading from the cowshed. Typically upon leaving the cow, milk will enter the pipe work which is under vacuum and this has a tendency to froth the milk resulting in damage to the solids within the milk and the high temperature also encouraging bacteria growth and reducing future milk shelf life expectancy.

After the pipe work the milk will typically be pumped to a heat exchanger such as a plate heat exchanger which creates shear in the milk which can cause cream or butter to form. The present invention therefore seeks to cool the milk at an earlier stage than the typical heat exchanger so as to avoid or at least minimise the above problems.

The present invention also seeks to improve the thermal efficiency of the milk cooling system which with better thermal energy recovery can enable less costly "cleaning-in-place", CIP, hot water.

Object of the Invention

It is an object of at least one embodiment of the present invention to provide a milk cooling system and method which can enable the cooling of milk in a timely, speedy and efficient manner or which at least will provide the public with a useful choice.

Further objects of this invention in its various embodiments will become apparent from the following description. Summary of the Invention

According to one aspect of the present invention there is provided a milk cooling means for the cooling, in use, of milk flowing through a pipe substantially immediately after its leaving a cow, said pipe providing an outlet means for milk received from one or more sets of teat cups, heat exchanging means being provided about the pipe to extract thermal energy from the milk in use flowing therethrough.

According to a further aspect of the present invention a method of milk cooling for milk flowing through a pipe includes providing the pipe as an outlet means for milk received from one or more sets of heat cups substantially immediately after its leaving a cow, and further providing heat exchanging means about the pipe to extract thermal energy from the milk in use flowing therethrough.

Optionally the heat exchanging means of either of the two immediately above paragraphs is in the form of a jacket.

Optionally the jacket may be in multiple parts adapted to be connected together about the pipe. Optionally a plurality of the jackets are adapted to be connected together in series along a length of the pipe.

Optionally the pipe is a vacuum header to which milk passes upon leaving a plurality of cows in a milking shed. Optionally the pipe is directly connected to a set of the teat cups to receive milk directly from a cow. Optionally the or each jacket includes flow disruption means to create a turbulence in the flow of cooling fluid, in use, through its one or more chambers.

Optionally the heat exchanging means includes a helically corrugated conduit or the like as a heat transfer surface.

According to a further aspect of the present invention a fluid cooling means and/or method is substantially as herein described with reference to any of the embodiments of the invention and with reference to the accompanying drawings.

According to a still further aspect of the invention a heat exchanging means is in the form of a jacket adapted to be provided about the pipe through which a first fluid will in use flow, said jacket provided with a fluid flow path through which a second fluid in use will flow to receive from, or transfer to, said first fluid, thermal energy Further aspects of this invention which should be considered in all its novel aspects will become apparent from the following description given by way of example of possible embodiments of the invention and in which reference is made to the accompanying drawings.

Brief description of the Drawings

Figure 1 : shows very diagrammatically one possible embodiment of the invention in use in a milking shed;

Figure 2: shows very diagrammatically a plan perspective view of one possible embodiment of the invention;

Figure 3: shows very diagrammatically a lower half of the embodiment of Figure 2;

Figure 4: shows very diagrammatically one possible embodiment of the invention in use within a cooling system; and

Figure 5: shows very diagrammatically a second possible embodiment of the invention in use within a cooling system.

Brief description of possible embodiments of the Invention

The present invention will be described hereinafter in respect of its particular use in the cooling of milk after leaving cows in a milking shed but as mentioned previously those skilled in the engineering arts will appreciate that numerous other uses would be possible; for example in respect of the production of beer, wine, fruit juices or indeed whenever a fluid is required to be cooled as part of a production or other process. It is also envisaged however that the heat exchanging means of the present invention could also be used for the transfer of heat energy to a fluid rather than its transfer from the fluid.

Referring therefore to Figure 1 , a plurality of cows (1) are shown being milked with their milk being taken from each cow shown in outline via a line (2) to a common vacuum header or pipe (3). The milk leaving the cows will be at a temperature of above 36°C but at least in New Zealand prior to it being collected it will need to be below TC Typically to date that cooling has been achieved by the milk travelling through the vacuum header to a plate heat exchanger. The delay in the milk being cooled can cause problems as mentioned previously. Plate heat exchangers are also typically complex and expensive.

As shown in Figure 1 however, a plurality of fluid cooling means, referenced generally by arrow (4), are shown sealed in position about the vacuum header (3). In the example shown, and referring also to Figures 2 and 3, the fluid cooling means may be in the form of a jacket or the like (5) having at least one chamber (6), (see Figure 3 particularly), providing a fluid flow path through which a cooling fluid such as chilled water can be caused to pass, the jacket (5) being provided with an inlet (7) and an outlet (8) for this purpose. The chamber (6) may also, as shown in Figure 3, be provided with turbulence creating means (14) such as turbulator spikes or the like which will disrupt the flow of cooling fluid as it passes through the one or more chambers (6) to enhance its cooling properties.

In the embodiment shown in Figures 2 and 3 jacket (5) is in the form of two parts with respective flanges (15) secured by screws, bolts or the like (16) so that the flanges (15), can be clamped together in defining a sealed chamber (6). Suitable seals, gaskets or the like may be provided as required in order to seal the chamber (6). In use the cooling fluid, such as chilled water, will be caused to flow in a direction indicated in Figure 1 by arrow A. In this embodiment a plurality of the cooling means (4) are positioned in series along the length of the vacuum header (3) and interconnected by pipes or hoses (10).

Referring then to Figure 4, in one possible embodiment the chilled water from a suitable source (9) flows in the directions indicated by arrows A and B along lines (23) and (22) respectively to the jackets (5) and to provide cooling for a heat exchanger (11), such as a tube-in-tube heat exchanger which may include a helically corrugated conduit as shown. The milk from the cows will be travelling in the direction indicated by arrow M, suitably to a receptacle (12), before it travels to the heat exchanger (11) as a counter-flow to the direction of the cooling fluid in the heat exchanger (11), to exit into a milk storage vat (13) in its cooled condition. The chilled water with the heat taken from the milk, is shown exiting in the direction indicated by arrows C and D in Figure 4.

It will be appreciated that the present invention, by providing for the cooling of the milk almost immediately it leaves the cows, is avoiding or at least minimising the problems associated with the frothing of the milk and bacteria growth. It is also enabling the use of the relatively inexpensive and less complex tube-in-tube heat exchangers for the further cooling of the milk before storage and also providing improved thermal efficiency for example by using the heated water for a CIP operation.

Turning now to a further possible embodiment of the invention, this is shown very diagrammatically in Figure 5. The same reference numerals as used in the preceding figures will again be used where appropriate.

The source (9) of cooling fluid is in this embodiment shown connected by line (23) with a common header (20) which supplies via lines (18) respective heat exchangers (17). These heat exchangers (17) are shown provided about respective milk lines (2) connecting the clusters of heat cups from each cow's milking station to the common vacuum header (3). The cooling fluid will counter flow through the exchangers (17) relative to the flow of milk through the milk lines (2) before passing through respective lines (19) to a common header

(21). The cooling fluid, now heated by the thermal energy from the milk, will exit the header (21) in the direction of arrow C when it can be utilised as the water for a CIP operation. The cooled milk collected in receptacle (12) will be further cooled in heat exchanger (1 1) before it is collected in vat (13). The chilled water with its counter flow through heat exchanger (11) relative to the milk flow is shown exiting again in direction indicated by arrow C to be utilised for a CIP operation if required.

The heat exchangers 1 1 and / or 17 may again utilise helically corrugated conduct as a heat transfer surface such as that described and claimed in New Zealand Patent No 255609 of Energy Saving Concepts Limited or may alternatively utilise straight tube or other forms of heat exchanger arrangements as will be well known to those skilled in this area.

Where in the foregoing description reference has been made to specific components or integers of the invention having known equivalents then such equivalents are herein incorporated as if individually set forth.

Although this invention has been described by way of example and with reference to possible embodiments thereof, it is to be understood that modifications or improvements may be made thereto without departing from the scope of the invention as defined in the appended claims.

Claims

1. A milk cooling system for the cooling, in use, of milk flowing through a pipe substantially immediately after its leaving a cow, said pipe providing an outlet means for milk received from one or more sets of teat cups, heat exchanging means being provided about the pipe to extract thermal energy from the milk in use flowing therethrough.

2. A method of milk cooling for milk flowing through a pipe including providing the pipe as an outlet means for milk received from one or more sets of teat cups substantially immediately after its leaving the cow, and further providing heat exchanging means about the pipe to extract thermal energy from the milk in use flowing therethrough.

3. A milk cooling system as claimed in claim 1 wherein the heat exchanging system is in the form of a jacket.

4. A milk cooling system as claimed in claim 3 wherein the jacket is in multiple parts adapted to be connected together about the pipe.

5. A milk cooling system is claimed in claim 4 wherein a plurality of the jackets are adapted to be connected together in series along a length of the pipe.

6. A milk cooling system as claimed in any one of the preceding claims wherein the pipe is a vacuum header to which milk passes from a plurality of cows in a milking shed.

7. A milk cooling system as claimed in any one of the claims 1 to 6 wherein the pipe is directly connected to a set of said teat cups to receive milk directly from a cow.

8. A milk cooling system as claimed in any one of the preceding claims wherein the heat exchanging means includes a helically corrugated conduit as a heat transfer surface.

9. A milk cooling system as claimed in any one of the preceding claims wherein milk flowing through the pipe in use is further cooled by a further heat exchanging means.

10. A milk cooling system as claimed in claim 9 in which the further heat exchanging means includes a helically corrugated conduit as a heat transfer surface.

11. A milk cooling system as claimed in claim 9 or 10 in which a source of cooling fluid is adapted to supply said cooling fluid to both said heat exchanging means.

12. A milk cooling system substantially as herein described with reference to figures 1 to 3, figure 4 or figure 5 of the accompanying drawings.

13. A method of milk cooling as claimed in claim 2 wherein the pipe is a vacuum header to which milk passes upon leaving a plurality of cows in a milking shed.

14. A method of milk cooling as claimed in claim 2 in which the pipe is directly connected to a set of said teat cups to receive milk directly from a cow.

15. A method of milk cooling substantially as herein described with reference to figures 1 to 3, figure 4 or figure 5 of the accompanying drawings.

16. A heat exchanging means in the form of a jacket adapted to be provided about a pipe through which a first fluid will in use flow, said jacket provided with a fluid flow path through which a second fluid in use will flow to receive from, or transfer to, said first fluid, thermal energy.

17. A heat exchanging means as claimed in claim 16 wherein the jacket is in multiple parts adapted to be connected together about the pipe.